Sprinkler systems using plastic or PVC (polyvinyl chloride) pipes have become widely used as a result of their low cost and ease of connection and repair. Such pipes, may be joined without threading by applying an adhesive such as a solvent cement to the ends of the pipes and slipping a pipe coupling over the ends.
However, installing new pipe and repairing sprinkler systems and broken pipes has traditionally been a difficult and complicated procedure. When a break occurs in an underground sprinkler system, the repair process has required isolating the break and then excavating around or otherwise clearing a long section of the PVC pipe surrounding the break. As disclosed in Zimmerman, U.S. Pat. No. 4,687,232, a long section of pipe on both sides of the break is required because the standard repair coupling until now has comprised a short piece of similar PVC piping which is radially enlarged relative to the pipe to be repaired and which is slipped and solvent welded over the broken ends of pipe. This requires that the broken ends of pipe be relatively free in order to have enough play to be bent back so that the weld coupling may be inserted and then the broken ends of pipe moved toward each other into the coupling. This method of bending and moving the pipe sections to be joined frequently results in an insertion of extra pipe length into the existing pipe line exerting additional stresses upon the pipe line. This problem is exacerbated in the instance of PVC pipe having a large diameter since in order to gain the required flexibility, a much greater length of pipe must be cleared on either side of the break. The same difficulties pertain wherein an additional branch pipe is to be added to an existing line since the existing pipe must be cut and a T-coupling inserted in the manner described above.
In repairing non-PVC pipe, the process is much more complicated. Frequently the entire length of pipe which is broken must be removed and a new length of pipe, if it is compatible, must be replaced and sometimes forced into place to fit the existing couplings. Otherwise, a torch cutting procedure must be employed and then a new length of pipe must be fitted and welded or otherwise heat fused into place.
In addition, the use of pipe couplings is not limited to the repair of sprinkler systems and other broken pipes. Pipe couplings are also in demand for new construction projects.
In repairing old sprinklers or completion of new construction, various devices have been developed and used. One solution has been the use of an extendable housing which is expensive. Alternatively, when repairing or completing a section of pipe, if a gap is left for removing a section of broken pipe or inaccurate measurements in new construction, using traditional pipe couplings, at least two pipe couplings and a length of pipe is needed to repair or complete the section of pipe. The present invention can repair or complete most of these sections with a single pipe coupling.
Accordingly, what is needed is a low cost, easy to use and effective means of coupling pipe ends for use with sprinkler systems, conduits in walls or fixed pipes in substrates, and other coupling of pipe ends.
Zimmerman, U.S. Pat. No. 4,687,232 discloses an in-line pipe coupling including a joint housing which encloses a piston means having a standard diameter pipe section which protrudes from one end of the joint housing that may be compressed and inserted into a small cutaway section of existing pipeline and then expanded to fit over the two free ends of pipe using a coupling on the sliding end to form a continuous water tight connection. The slip joint may be utilized in conjunction with either a standard or straight pipe coupling or a T-coupling or cross coupling in order to facilitate addition of one or more branch lines to an existing pipeline.
Curtain, U.S. Pat. No. 4,109,944 discloses a coupling for unthreaded pipes of a sprinkler system, which permits the replacement of a small damaged pipe section without bending the pipes already emplaced in the ground. The coupling includes a pair of semi-cylindrical pipe sections adapted to fit around and engage the emplaced pipes. The longitudinal edges of the two semi-cylindrical pipe sections are formed so as to mate with one another to hold the sections together as an applied adhesive forms a water tight seal.
It would be highly desirable to provide an easy to use and cost-effective way to repair or connect pipe ends.
This invention provides a simple, low-cost way of repairing or completing the assembly of pipe ends.
In accordance with one aspect of the present invention, a pipe coupling includes an elongated housing having a first end and a second end, the housing defining an elongated cylindrical bore therein; a stop located on an inner diameter of the housing, the stop located between the first end and the second end of the housing; and wherein a distance from the stop to the first end of the housing is greater than a distance from the stop to the second end.
In accordance with another aspect of the present invention, a pipe coupling includes an elongated housing having a first end and a second end, the housing defining an elongated cylindrical bore therein; a stop located on an inner diameter of the housing, the stop located between the first end and the second end of the housing; wherein a distance from the stop to the first end of the housing is greater than a distance from the stop to the second end, the housing having a length of between about 3xc2xd and about 5xc2xd inches.
In accordance with a further aspect of the present invention, a method for using a pipe coupling includes the steps of inserting a first end of the pipe coupling onto an end of a first pipe, the pipe coupling having an elongated housing having a first end and a second end, the housing defining an elongated cylindrical bore therein, a stop located on an inner diameter of the housing and between the first end and the second end of the housing, and wherein the distance from the stop to the first end of the housing is greater than the distance from the stop to the second end; advancing the pipe coupling in a first direction onto the first pipe; aligning the second end of the pipe coupling with an end of a second pipe; and advancing the pipe coupling in an opposite direction onto the second pipe until the stop reaches the end of the second pipe.